Energy absorber between vehicle roof and headliner

Abstract

An assembly for a vehicle includes a vehicle roof and a headliner supported by the vehicle roof. The assembly includes an energy absorber between the headliner and the vehicle roof. The energy absorber includes a wall extending transversely to the headliner and the vehicle roof. The wall includes a lattice structure including a repeating pattern of strips and open cells.

The invention claimed is: 
     
       1. An assembly comprising:
 a vehicle roof; 
 a headliner supported by the vehicle roof; 
 an energy absorber between the headliner and the vehicle roof, the energy absorber having a wall extending transversely to the headliner and the vehicle roof; 
 the wall having a lattice structure including a repeating pattern of strips and open cells; 
 the energy absorber including additional walls extending transversely to each other and transversely to the headliner and the walls defining a cavity therebetween; 
 the open cells extending through the wall from the cavity to an exterior of the energy absorber; 
 the energy absorber including an end panel connected to the walls and extending across the cavity and a base distal to the end panel, the cavity being open at the base, the end panel abutting one of the vehicle roof and the headliner and the base being adhered to the other of the vehicle roof and the headliner; and 
 the lattice structure including a vehicle-inboard end and a vehicle-outboard end, the open cells having a volume at the vehicle-inboard end and a volume at the vehicle-outboard end different from the volume at the vehicle-inboard end. 
 
     
     
       2. The assembly of  claim 1 , wherein the energy absorber is polypropylene. 
     
     
       3. The assembly of  claim 1 , wherein at least one of the additional walls includes the lattice structure. 
     
     
       4. The assembly of  claim 1 , wherein the base is shaped to match contours of the other of the vehicle roof and the headliner. 
     
     
       5. The assembly of  claim 1 , wherein the end panel is shaped to match contours of the one of the vehicle roof and the headliner. 
     
     
       6. The assembly of  claim 1 , wherein the lattice structure includes a first portion and a second portion, the strips having a height at the first portion and a height at the second portion different from the height at the first portion. 
     
     
       7. The assembly of  claim 1 , wherein the wall includes a vehicle-inboard end having a stiffness and a vehicle-outboard end having a stiffness, the stiffness at the vehicle-inboard end of the wall being greater than the stiffness at the vehicle-outboard end of the wall. 
     
     
       8. The assembly of  claim 7 , wherein the strips have a height at the vehicle-inboard end of the wall and a height at the vehicle-outboard end of the wall different from the height at the vehicle-inboard end of the wall. 
     
     
       9. The assembly of  claim 7 , wherein the open cells have a volume at the vehicle-inboard end of the wall and a volume at the vehicle-outboard end of the wall, the volume at the vehicle-outboard end of the wall being greater than the volume at the vehicle-inboard end of the wall. 
     
     
       10. An energy absorber comprising:
 an end panel; and 
 at least three walls extending in a common direction from the end panel and defining a cavity therebetween; 
 the walls defining a base distal to the end panel, the cavity being open at the base; 
 the end panel designed to match contours of one of a vehicle roof and a vehicle headliner; 
 the base designed to match contours of the other of the vehicle roof and the vehicle headliner; 
 at least one of the walls extending transversely to the headliner and the vehicle roof and at least one of the walls having a lattice structure including a repeating pattern of strips and open cells; 
 the open cells extend through the walls from the cavity to an exterior of the energy absorber; 
 the end panel abutting one of the vehicle roof and the headliner and the base being adhered to the other of the vehicle roof and the headliner; and 
 the lattice structure including a vehicle-inboard end and a vehicle-outboard end, the open cells having a volume at the vehicle-inboard end and a volume at the vehicle-outboard end different from the volume at the vehicle-inboard end. 
 
     
     
       11. The energy absorber of  claim 10 , wherein the walls include a first end having a stiffness and a second end having a stiffness different from the stiffness of the first end.